Traumatic cardiac arrest in the emergency department - Overview upon primary causes.

RATIONALE
Trauma is the leading cause of death for patients aged less than 40 years. Trauma patients with cardiac arrest have low survival rates, the resuscitation being often considered futile and consumptive of medical and human resources.


OBJECTIVE
The aim of this study is to describe the main characteristics in cases of patients critically traumatized, who were admitted in our emergency department.


METHODS AND RESULTS
The study is based on a retrospective analysis of cases of major trauma admitted in an Emergency Department between 2004 and 2008. There were 201 cases of critically traumatized patients, who received cardiopulmonary resuscitation. The patients were aged between 16 and 79, mostly men (67.16%), with a range of ISS between 30 and 75. Regarding the type of mechanism that produced the injury we noted a predominance of blunt trauma (87,2% of cases) and hypovolemia as a direct cause that led to the cardiac arrest. The first monitored rhythm was non-shockable for over 90% of the cases. In our group, 4 patients were discharged alive (2% of all cardiac arrest cases). The mechanism of cardiac arrest for those 4 cases were hypoxia through massive facial trauma in one case and tension pneumothorax through severe thoracic trauma in three cases.


DISCUSSION
Given the low survival figures, all the efforts that could be achieved by an emergency team in the face of severe trauma had to be oriented towards the maintaining of the vital functions or, when needed, towards restoring life in order to enrich the operation theatre for the definitive care.


Introduction
Trauma is the leading cause of death for patients aged below 40 years [1]. Chest injuries, injuries of the heart and of the great vessels are responsible for about 25% of the post-traumatic deaths and count as an aggravating factor for another 25% of the trauma-related deaths [2]. Patients with cardiac arrest caused by any condition may have survival rates up to 17% after cardiopulmonary resuscitation [3], whilst trauma patients with cardiac arrest, as most studies show, survive only in rates of 0% to 3.7% [4]. Therefore, resuscitation in trauma patients is considered by many respectable researchers to be futile and consumptive of medical and human resources, especially in the field and in case of multiple victims [5]. National Association of EMS Physicians and American College of Surgeons Committee on Trauma have produced guidelines that sustain withholding resuscitation in out-of-hospital setting of posttraumatic cardiac arrest [4]. Early recognition and treatment of causes leading to cardiorespiratory arrest may improve the patient's outcome and prevent cardiac arrest.
The aim of this study is to describe the main characteristic causes in cases of patients critically traumatized who were admitted in our emergency department. Based on the survival rates, a predominance of a certain cause of cardiac arrest was established, characteristic of survival patients, we had to concentrate the resuscitative efforts so that to delay the occurrence of cardiac arrest and to treat the cause.

Methods
The study is based upon a retrospective analysis of cases of major trauma admitted in the emergency department of "Sf. Pantelimon" Emergency Hospital in Bucharest between 2004 and 2008. The patients admitted in the study were adults (aged over 16), critically traumatized, who suffered from cardiorespiratory arrest in the emergency department. All the patients received cardiopulmonary resuscitation according to resuscitation The population represented by the cases included in the study showed that men are more frequently exposed to this kind of events, the median age found was 41, and asystole was the first monitored rhythm for most of the patients. These characteristics are similar to the ones described in larger studies [8].
It can also be said that ISS measured severity of trauma correlated with the most active ages, socially speaking, as, in our study the younger patients were given a higher ISS score.
The insertion of the chest tube for the tension pneumothorax proved to be survival factor, such as 3 of the alive discharged patients in our study benefited from the maneuver. This situation is mentioned as a strong prediction factor in the survival in traumatic cardiac arrests [9].
The different correlations between certain variables in order to assess the probability of the presence of a certain cause in face of a certain condition are interesting things to observe. Therefore, it can be revealed that hypovolemia characterizes the main mechanism of cardiac arrest in case of penetrated traumatisms and blunt trauma and crush trauma as well, being the leading cause of collapse among the all causes analyzed. This observation is confirmed by studies and guidelines, as well [10].
Given the low survival figures, all efforts that could be achieved by an emergency team in the face of severe trauma, no matter the place, the appreciated risk of survival, in terms of age, of gravity of lesions (ISS or other scores), the supplies or quality of training, must be oriented to maintaining the vital signs, the vital functions or, when needed, to restoring life in order to enrich the operation theatre for final treatment, definitive care.